I would say that expectations don't turn a bad game on a good game or vice-versa.
But when you don't expect anything of anything them if that don't happen or is bad you don't feel as bad.
Also yes high expectations can lead something that is great in good on your opinion because of your high expectation not being met (like some stuff not being in the game that you expected to have).
duduspace11 "Well, since we are estimating costs, Pokemon Red/Blue did cost Nintendo about $50m to make back in 1996"
http://gamrconnect.vgchartz.com/post.php?id=8808363
Mr Puggsly: "Hehe, I said good profit. You said big profit. Frankly, not losing money is what I meant by good. Don't get hung up on semantics"
http://gamrconnect.vgchartz.com/post.php?id=9008994
Azzanation: "PS5 wouldn't sold out at launch without scalpers."